1. Field of the Invention
The present invention relates to a light device and a positional information management system.
2. Description of the Related Art
Various positional information management systems have been proposed to determine and manage the position of a wireless terminal, or a person or a thing which has a wireless terminal, in such a facility or the like in which it is difficult to accurately carry out positioning using GPS or the like.
In such a positional information management system, a plurality of transmitters for transmitting positional information to the wireless terminals are installed on the ceiling of a room or the like for example. However, for this purpose, new power supply installation work is needed for supplying the power to the transmitters, and thus, the introduction cost may be increased.
International Patent Publication No. 2005/086375 discloses a system in which the position of the wireless terminal is determined as a result of the wireless terminal receiving unique information from a light device and transmitting the unique information to a server. Further, an idea has been studied for placing a wireless communication device for carrying out communication with the wireless terminal, a positional information transmitter, a voltage circuit part and/or the like inside the light device that is a tubular body such as a straight tube fluorescent lamp, for the purpose of simplifying the configuration, laborsaving in the necessary work and/or the like.
However, in the above-mentioned light device, in a case of placing a wireless communication device and a positional information transmitter including antennas inside the tubular body, the wireless communication device and positional information transmitter are to be placed near a metal cap part formed at an end of the tubular body for preventing the light from the light source from being obstructed. In this case, the transmission area of the positional information transmitter when communication is carried out with the wireless terminal may be limited by the metal cap part.